1. Field of the Invention
The present invention relates to a recording and reproducing apparatus, and more particularly to an apparatus for recording and reproducing television signals of a plurality of multiplexed programs each constituted of a plurality of packets.
2. Related Background Art
Digital television (hereinafter described as digital TV) broadcasting for broadcasting television signals as digital signals has been proposed recently, and in Japan, it is realized already as CS (Communication Satellite) broadcasting.
An apparatus for receiving digital TV broadcasting signals and recording and reproducing them will be described.
FIG. 16 is a block diagram showing an apparatus for receiving digital TV broadcasting signals and recording and reproducing them.
In FIG. 16, a digital TV signal received by a tuner 1601 is input via an input line 161 to an SW circuit 1603 and a data control circuit 1615. The data control circuit 1615 counts and stores a bit rate of the received data, and controls a data storage 1617 via a control line 1621-9 to store the received data via an input line 170. The data storage 1617 may be a hard disk, a large capacity semiconductor memory, an optical recording device, a magnetic recording device or the like.
While the received data is recorded, the received data may be divided, decoded and output. Namely, the received data input to the SW circuit 1603 via the input line 161 is selected by the SW circuit 1603 and input to a demultiplexer 1605 via an input line 162.
The demultiplexer 1605 picks up only the data of a designated program in accordance with an ID in the received data, and divides it into a video data train and an audio data train. Video data is input via a video data line 163 to a video decoding unit 1607, and audio PES packet data is input via an audio PES data line 164 to an audio decoding unit 1609.
The video decoding unit 1607 decodes the input video data train in a manner corresponding to the encoding executed when the data was transmitted, and outputs the decoded data to a video control unit 1611. The video control unit 1611 converts the decoded video data into a format suitable for external apparatus which is not shown, and outputs it via an output line 167. The audio decoding unit 1609 decodes the input audio data train in a manner corresponding to the encoding executed when the data was transmitted, and outputs the decoded data to an audio control unit 1613. The audio control unit 1613 converts the decoded audio data into a format suitable for an unrepresented external apparatus, and outputs it via an output line 168.
Next, an operation of reproducing data recorded in the data storage 1617 will be described.
The data control unit 1615 controls the data storage 1617 via the control line 1621 or the like to read the recorded digital TV data and outputs it to the SW circuit 1603 via an input line 169 at the bit rate stored in the data control unit 1615 when the TV data was received. When the digital TV data recorded in the data storage 1617 is divided, decoded and output, the SW circuit 1603 selects the data input via the input line 169. The selected data is input to the demultiplexer 1605 via the input line 162. The operation to follow is the same as described above.
The recording and reproducing apparatus described above is, however, associated with some problem. Namely, since the received data is recorded in or reproduced from the data storage on the program unit basis, when the data recorded in the data storage is reproduced, it is only possible either to reproduce the data from the start of a program or to reproduce the data from a proper position (in the unit of a management file of the data storage) intermediately of the recorded TS packet. The data cannot be reproduced from the position desired by a user, i.e., a so-called random access reproduction is impossible.